Cam-operated clamping device



June 7, 1960 s. ROTHMAN CAM-OPERATED CLAMPING DEVICE 2 Sheets-Sheet 1 Filed July 23, 1958 AWOHVZIY June 7, 1960 s. ROTHMAN 2,

CAM-QPERATED CLAMPING DEVICE Filed July 23, 1958 I 2 Sheets-Sheet 2 INVENTOR.

7-f- I STANLEY ROTHMAN BY W fcAMmrERA-Tiin CLAMPn IG nnvlcnl I I Filed July 23, 195s. s t. N 758,468 1 rcaas I. s #ii4 4iiii1;.

This invention relates to the-art of clamping devices; and particularly. concerns anovel cam-operated device to be engaged, as shown in Figs.2and 6.

25939 565 Fu s June 7, 196g the metal strip is partially-encased in a resilient rubber sheath 16. =Ends 18; arid20 of'the band 14 extend I are closed and locked by beyond the sheath'and-are ofiset to extend substantially tangentially tothe pipewhen the endsof'th'e band the clamping device, as b est showninFig. 5.--.-.;.. I

' Registering apertures 22'- and24 are provided in the I ends' 18-and-20 of the band. 'The flat plate or 'bar- 12 which may be elongated is provided with a circular aperture 26 at the location where they clamping device *is The clamping deviceinclud'es a-fulcrum post 'or 28 having a generally cylindrical shank 29 with opposite fonclamping a pipe to aflat surface,- plate or'the like.

' According to the invention, there is provided a clamping; device of general utility adapted to'encircle and secure a cylindrical rod or tubular pipe to a flat surface.

A:-principalobject is to provide a clamping device flattened sides 30 extending from the free end thereof. The other end of the pin terminates in a dish-shaped circular head 32 having spaced peripheral radial slots 34. The shank has a bearing notch 36 in onelong edge 1 at its free end to form'a hook 38, as clearly shown in whichcan be disassembled and reassembled as and where 1 required upon apipe which may. be stationary -'A further object is to provide a :clampingdevice including a lever-operated cam member detachably engaged with aclamping'member.

, fiForfurther comprehension of 'the inventiomand of the objects1 and advantages. thereof, reference will be hadto the following; description and accompanying draw.- ings; and to;the appendedzclaims'in which the various novel features of the invention ,are more particular-1y set fOl'lh." I 1 T 1 In the accompanying drawings forming a material part of*this;disclos'ure: ,7 x Q g wFigul is a perspective view'of the clampingjdevice embodyingthe. invention securing; a pipe to a flat plate.

@Eig. -2.-is an exploded perspective view of the components includedin the-assembledcomponents of Fig. 1. Fig.5 3; is aside elevational viewz-of the assembly with thei'clamp'. unlocked." 7 1 1 p i Fig. 4 is a view similartoFig'; 3 with the clamp locked. 2. Fig.5 is an end elevationalview of the locked assembly of Fig.'4.l r r V ,Fig; 6 is .a-sectional=.view onan enlarged scale taken onjlinefi:6 6 of Fig. 5 and showing details-of theclampingfcomponents; v l

1 Fig.7 is a topplan view onan enlarged scale of partofthe assembly of Fig; 5.

.--Fig; 8 is an enlarged b ttomplanv1ew;of;tlie:fulcrum Fig. 12 is alsimilar view showing the position of the partsat the end of the closing rnovement of theca'm membeh Fig.4 a vertical sectionalview showing a modification ofitheminvention. i v i Fi'g'.jsl,4, is a similarview to Fig. 13, showing a still plane of the u the fi e i e m o t inv ion,-

Referringto Figs. l-5.of the drawings,'there isjshown a cylindricalor tubular member '10 which can be a pipe,

rod'or similar member, which is to be detachablyse cured to a flat plate or barf12. a

' split band' l4'formed preferably of a metal strip is provided to' ncircle theround member 10. Ifpipe' 10"is inade of a relatively soft material such as plastic,"

Fig. 6.

The clamping device also includes a cam member 40 formed with two parallel plates constituting walls 42 having semicircular or 180 outer edge portions 44 ter minating at points A where the edges become straight and extend tangentially to edge portions 44 as shown at 45. The walls are joined by an integrally formed U-shaped bridge '46. The bridge is undercut to provide straight edge portions 48 on each wall extending chordally and terminating at curved portions 44. The straight edge portionsmay be provided with teeth or otherwise serrated or roughened. In the bridge. or bight portion 46 of the cam member 40 there is secured a handle 50 which extends outwardly from the member parallel to walls 42. A shaft or axle 52 extends transversely across the space between the walls 42 near the'corners of the walls where the straight edge portions 48 join the curved edge portions 44. The bearing notch 36 of pin or post 28 is adapted to fit'over the shaft 52 so that the cam member .40 may turn on the pin 28. i Fig. 6 shows the shaft 52 extending through the notch 36: and Fig.' 7 shows flat sides 30 of post 28 disposed between walls 42 of the cam member 40 with shaft 52 extending therethrough.

In- Fig. Zthere are shown the several components of the assembly. Band 14 can be inserted over an end of 'inserted through apertures 26, 24; and 22, in turn. The

notch portion 36 of the shank extends upwardly from band end-18 so thatshaft 52 of member 40 can be en gaged therein with the handle 50 in the depend-ing position shown in. Fig. 3. The serrated edge portions 48 of wails 42 will then bepressedagainst the outer side of band end '18 because of the upward bias of this end due to the spring-like structure of the band. -In this position band ends 18an d 20 are separated and the clamping device is unlocked as shown in Fig. 3.

In order to lock the clamping device, the shaft 5 carrying the cam member 40 is turned manually in bearing notch 36 offulcrum post 28 anticlockwise as viewed in Fig. 3 by finger pressureon handle 50. A 180 turn of the shaft and cammember 40 from the position of Fig. 3 first moves the curved portions or cam ming faces 44 of walls 42 of the cam member over the upper side of band end 18 until the straight edge portions 45 are reached at points A. A further turn brings the edge portions 45 against the band 18 to lock the cam member securely in the position shown in Figs. 1, 4, 5, 6, and 7. Since shaft 52 is located near the comers where the edge portion 44 ad 48 meet, the walls 42 rotate on or swing about an eccentrically located axis. Points A are the ends of the longest radii of the cam plates from shaft 52. The pressure on hand end 18 increases as the cam member is turned from the shortest radii of the cam walls to the longest radii at points A, due to the increasing tension in band 14 as band end'18 is forced to ward the band end 20. Dimple, protrusions 54 on the inner surfaces of walls 42 engaging the sides of the fulcrum post 28 prevent accidental opening of the cam member 4ft.

In order to make the clamping action effective in the device, the length of the shank of pinor post 23 from the inner end of notch 36 to the head 32 should not be less than the length of the maximum radius of the cam member walls 42, plus the combined thickness of band ends 18, 2t) and of plate 12.

If desired, the cam member 44) can be pivoted when 1n the locked position on pin '28 using the cylindrical shank portion thereof as an axis. so that handle 50 extends perpendicular to the axis of pipe rather than parallel to it as shown in the drawing. If pivotal movement of the locked cam member is not desired, thetopening 26 in bar '12 will be shaped square instead of round and the shank portion 29 can be formed with fiat sides 34 extending downwardly so that they are juxtaposed to new, and desire to secure by United States Letters Pat out is:

1. A clamping device forsecuring a tubular member and a flat apertured plate together, comprising a split band formed of a spring metal strip adapted to encircle said tubular member, the free ends of said band being apertured and being offset to extend substantially tangentially to said tubularmember, a fulcrum pin having a terminal head and a generally'cylindricalshank, said shank being extendible through the apertures in said plate and band ends with said apertures in registration with each other, said shank terminatingin a bearing notch, and a cam member having a transversely disposed shaft 7 removably engageable in said bearing notch of said shank the sides of square aperture 26 in bar 12. Then the pin 28 will be locked against rotation with respect to the bar 12 and pipe 10.

The clamping device is so constructed that pin 28 and clamp, member dtl can be quickly disassembled and band M can be disengaged Without disturbing pipe alt Thus, if pipe it) is a long member, it can be secured to bar 12 at any desired intermediate point on the pipe without disconnecting the pipe from an end support to effect the mounting of the clamping member.

Bar 12 as well as pipe 10 could be elongated and the clamping device will be quickly attachable thereto and detachable therefrom in the same manner as described above. If desired, the bar 12 can be secured with its long axis parallel to the axis of pipe 10 rather than perpendicular thereto.

In the modification shown in Fig. 13, a pipe 10 is shown fastened to the undersurface of a plate 112' by means 0 a modified clamping device. The modified clamping device consists of a flat metal strip 60 or circular cross-section rod of U-shaped formation open at the top with its ends extending through spaced slots 62 formed in the plate 12'. At one of the protruding ends 64 of the strip, or rod, the inner longedge thereof is formed with a notch 66 opening inwardly and forming a hook 68 thereabove. The other protruding end 64 of the strip or rod 60 is similarly formed with a notch 70 in the outer long edge and opening outwardly thereof to form a hook '72 thereabove.

A cam member '40 spans each of the protruding ends 64 with its shaft 52 journalled in the respective notch 66 or 76 so that turning of the shaft by the handle 50 brings the curved peripheries 44 of the walls 42 thereof into locking engagement against the upper surface of the plate 12' as shown in Fig. 13. In order to open the clamp, the cam member is turned in the opposite direction.

In Fig. 14, a single stem 80 is shown to lock plates 12" together by a cam member 40 as previously described.

The clamping device disclosed requires no tools to attach or loosen. No threading of the clamping member is required to tighten it as in prior known types of clamping members.

. While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and that various changes and modifications may be made within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as so that the cam member is turnable with respect to said pin to draw said band ends together under spring tension therein, said cam member including two parallel plate portions joined by an integrally formedbridge portion, saidshaft terminating at eccentric positions on said plate portions, each of said plate portions having a curved edge portion extending less than 360 from a point near said termination. of the shaft to a point of maximum radius of said plate portion from said shaft, each of said plate portions having a substantially straight edge portion extending substantially tangentially from said curved edge portion from said point of maximum radius,said'substantially straight edge portions-being continuous across said bridge portion, said bridge portion being undercut to provide substantially straight serrated edge portions on each blade extendingchordallyto terminate at said curved edge portions, there being a handle extending outwardlyfrom said bridge portion for pivoting said cam member on said shaft, said shank having flat side portions adapted to move slidably between said parallel plate portions, said flat side portions being extended to engage in the aperture insaid flat aper'tured plate, the aperture in said plate being square to prevent rotation of the pin therein, said shaft being held in said recess in abutment with an inner end of the notch when the cam member is locked by spring tension in said'band ends, said shank having a length from the inner end of the bearing notch to said head which is not less than the lengthof the maximurn radii of said plate portions plus the combined thickness of said band ends and flat plate. 9

2. A clamping device for securing a tubular member and a fiat apertured plate together, comprising a split band formedof a spring metal strip adapted to encircle said tubular member, the free ends of the-band being apertured and offset to extend substantially tangentially to said tubular member, a fulcrum pin having a terminal head and a generally cylindrical shank, saidshank being extendible through the apertures in said plate and band ends with said apertures in registration with each other,

said shank terminating in a bearing notch, and a cam member having a transversely disposed shaft removably engageable in said recess of said shank so that the cam member is, turnable with respect to said pin to draw said band ends together under spring tension therein, said cam member including two parallel plate portions joined by an integrally formed bridge portion, said shaft tel minating at eccentric positions on said plate portions, each of said plate portions having ,a curved edge portion extending less than 360 from a point near said termination, of the shaft to a point of maximum radius of saidplate portion from said shaft, each of said plate portions having a substantially straight. edge portion extending substantially tangentiallyfrom said, curved edge portion from said point ofmaximum radius, said substantially straight edge portions being continuous across said bridge portion, said bridge portion being undercut to provide substantially straight serrated edge portions on each blade extending chordally to terminate at said curved edge pertions, said flat side portions being extended to engage in the aperture in said flat apertured plate, said shaft being held'in said notch in abutment with a hooked end of the notch when the cam member is locked by spring tension in said band ends, and dimpledprotrusions on the inner surfaces of the walls of the cam member holding said cam member against accidental displacement.

References Cited in the file of this patent UNITED STATES PATENTS Lang Dec. 28, 1886 Atkinson June 3, 1902 Thomas Oct. 26, 1954 FOREIGN PATENTS Italy Mar. 13, 1947 

